covid-19 vaccine

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ATLANTA, Ga. — The coronavirus vaccine has been a lightning rod topic for over a year. Many people who continue to resist vaccination efforts cite their concerns over the possible side-effects getting the shot could produce. Now, a new study is trying to put those fears to rest for good. Researchers with the Centers for Disease Control and Prevention have found that over 90 percent of the people suffering a reaction to a COVID mRNA vaccine only experienced mild and temporary side-effects from the shot.

In a study examining the reported reactions to vaccine doses distributed throughout the United States, researchers found that 92 percent had side-effects listed as non-serious. The findings come from a review of the more than 340,000 reports of vaccine side-effects out of 298 million COVID vaccine doses administered between December 2020 and June 2021.

Out of the 313,000 patients reporting mild reactions to the vaccine, 20 percent reported experiencing headaches after injection. Other side-effects included fatigue (17%), fever (16%), chills (16%), and pain (15%). The two mRNA COVID-19 vaccines – Pfizer-BioNTech (BNT162b2) and Moderna (mRNA-1723) – teach a recipient’s cells how to make a protein that triggers an immune response inside the body.

Vaccines are the most effective tool to prevent serious COVID-19 disease outcomes and the benefits of immunization in preventing serious illness and death strongly favor vaccination,” says study author Dr. Hannah Rosenblum of the CDC in a media release. “COVID-19 vaccine safety monitoring is the most robust in US history and the two complementary surveillance systems used in this study should bolster confidence that mRNA COVID-19 vaccines are safe.”

Second shot is worse than the first

Researchers used two main sources to track the vaccine side-effects during the coronavirus pandemic. One is the Vaccine Adverse Event Reporting System (VAERS), an established reporting system run by the CDC and U.S. Food and Drug Administration. U.S. residents, healthcare providers, and vaccine manufacturers can all submit their observations to VAERS after taking or distributing a vaccine dose.

The second source is v-safe, a system run by the CDC, created during the COVID vaccine rollout. It uses a smartphone-based survey to track potential side-effects in the first week after someone receives their COVID shot.

Overall, study authors found more people experiencing vaccine side-effects reported having a reaction after their second dose. Of the nearly eight million v-safe participants in the study, 34 percent experienced fatigue after dose one, while 56 percent had this side-effect after dose two. Headaches nearly doubled between dose one (27%) and dose two (46%), while injection site pain stayed roughly the same (66% and 69%, respectively).

More v-safe participants also reported being unable to work temporarily or needing medical care after receiving the COVID vaccine’s second dose (32%) than the first one (12%).

“VAERS and v-safe are important tools CDC can use when evaluating vaccine safety and to help identify any unexpected or unusual events. These data are reassuring that reactions to both mRNA vaccines are generally mild and subside after one or two days—confirming reports from clinical trials and post-authorization monitoring,” adds study author Dr. Tom Shimabukuro.

What are the most common severe side-effects?

Despite the vast majority experiencing mild side-effects for the COVID vaccine, more than 22,000 vaccine recipients reported side-effects researchers classified as serious. The most common reaction was shortness of breath (15%). Roughly 4,500 people died after receiving the vaccine, with more than 80 percent being over the age of 60.

The team cautions that healthcare providers must report any death taking place following vaccinations, regardless of a direct link or not. The new study, however, did not find a pattern between these deaths and something specific in the COVID vaccines.

“The rapid pace at which COVID-19 vaccines were administered under emergency use, especially among older populations, was unprecedented. Due to their age, this group already has a higher baseline mortality rate than the general population and our results follow similar patterns of deaths rates for people in this age group following other adult vaccinations,” says study author Dr. David Shay.

“Reassuringly, the six-month VAERS data supports that, although approximately one in 1,000 individuals vaccinated may have an adverse effect, most of these are non-serious. No unusual patterns emerged in the cause of death or serious adverse effects among VAERS reports… For adverse events of special interest, it is reassuring that there were no unexpected signals other than myopericarditis and anaphylaxis, already known to be associated with mRNA vaccines,” concludes Elizabeth Phillips from Vanderbilt University Medical Center, who did not take part in the study.

The findings are published in the journal The Lancet Infectious Diseases.

About Chris Melore

Chris Melore has been a writer, researcher, editor, and producer in the New York-area since 2006. He won a local Emmy award for his work in sports television in 2011.

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